Unfortunately the phrases hidden gem and Adelaide's best kept secret pop up so often in articles that they are virtually meaningless. Normally encountering those phrases is enough to make me stop reading and move on to something else.

But I have made a few discoveries that have surprised me. Some friends were unaware of the Stirling Linear Park even though they only lived a kilometre or two away for years.

And mea culpa, I had never heard of Randell Park in Mitcham even though I lived a few kilometres away from it too. It was only after I Googled for somewhere different for me to walk my dog that I stumbled across this huge park just down the road from Scotch College.

It is a large park that stretches from Mitcham in the west to Belair in the south and east. It is hilly in most areas, although not all steep. It's easy to take a walk around the lower areas without working hard, although the higher areas tend to be steeper.

For a couple of years around 2002 Randell Park was popular with mountain bike riders, but Mitcham Council banned bikes in the park after complaints from residents. It was also found that the bikes were causing too much erosion on steeper hills.

However that may be about to change - it seems that the council is working to provide bike access trails in the park soon.

At the moment the Randell Park is mostly used by locals either jogging or walking their dogs.

I entered the park at the Braemar Road entrance and followed the fire track to the right up a gentle slope. A few hundred metres in some council workers were clearing undergrowth to reduce fire risk, and they helpfully told me more about the park layout.

The fire trail ends at a small quarry a little further on, but a narrow walking trail then winds its way upwards around the quarry, exposing walkers to some great views of Glenelg to the west and the city to the north. About 10 minutes walk further the path comes alongside the top of a much larger quarry which is fenced off. The views are not as good here, being blocked by trees.

I was told that it is possible to walk around the larger quarry to the Anderson Road entrance, or deviate to the right and reach Burnell Drive in Belair. (Access on Burnell Drive is through a pedestrian-only gate to prevent mountain bike riders from using the park). Unfortunately the Mitcham Council website gives no information about trails in the park, but talks a bit about the geology and history.

On retracing my way down, I didn't hear as many bird calls high on the hill than I did in the flatter area. Predictably each time I tried to record them on a video, the birds quietened. I did find a colourful pair of rainbow lorikeets busily working on their nest in a hollow though.

The next day I came back to explore the western part of the park near Anderson Avenue, but climbing uphill there led to private property and a guard dog. The middle section of the park was more rewarding, although it became fairly steep and a little rocky.

As I returned to the car a Trees For Life volunteer was spraying nasturtiums to prevent their spread in Randell Park. He was just near a drystone wall which may have been used to dam the watercourse, or as part of the quarry workings.

There are no facilities in the park, but stacks of free firewood are left around by council workers - a bonus for winter visitors. Both the dog and I really enjoyed the park, I let him off leash as there were no signs indicating otherwise, and nobody else near me.